[themyst]

I have been discussing the impact of modifying cam angles et al on a flash tune with a stage 2 beta tester.

My question is can this be possible on a piggyback and if it is, why hasn't it been implemented?

[Clap135]

Currently not possible, but don't worry v5 r4.0 is coming out anyday now, which means one week from that day terry will go to isle 7 in radio shack and post directions of how to steal it.

[enrita]

Originally Posted by Clap135

Currently not possible, but don't worry v5 r4.0 is coming out anyday now, which means one week from that day terry will go to isle 7 in radio shack and post directions of how to steal it.

[BMWsky]

Oh my.

[bulldog_yyc]

are cam angles modified with any of the current flash tunes?

[themyst]

Originally Posted by turkish335

are cam angles modified with any of the current flash tunes?

Yes, the upcoming Cobb stage 2.

[BMWsky]

Not to be a total rube here, but could someone give the Readers Digest version of how it works and what type of gains are experienced?

[EastBayE90]

We used to play with cam angles all the time on K-Pro for the Honda K-Series engines. I have wondered why we haven't been able to play with the angles yet on the N54. What would it take to be able to adjust cam angles with a piggy?

[themyst]

If there is a pin on the dme that controls cam angles or intake/exhaust valves, theoretically should be possible on a piggyback. I don't have that kind of technical knowledge though.

[vasillalov]

There is no reason to play with the cam angles unless you have upgraded turbos or big turbo. In NA engines, different camshaft profiles allow you for different amount of valve lift and also different amount of time during which a valve is open. All this is done to improve the speed at which air and fuel enter the combustion chamber. The point of it is to maximize the suction effect of the engine (volumetric efficiency). Equal length intake runners, velocity stacks, individual throttle bodies, those are all things that help with volumetric efficiency. You don't just bolt things together and hope for the best. You need to know what your engine is capable of, how much the head flows and heck of a lot of other things before you can maximize power output.

Turbo engines share a lot of these aspects with the NA engines except that you want to maximize the volumetric efficiency when the turbos are delivering the most volume of air. So, our current VANOS is tuned for stock turbos because their parameters are well known. Upgraded turbos and bigger turbos have different flow characteristics and the engine will have a different volumetric efficiency because of that.

I am not saying that playing with the VANOS won't give you any positive results on the N54. I am saying that one has to do a lot of calculations and/or testing on a turbo engine. I'd probably look into upgrading the cams and porting the head first.

[BMWsky]

Thank you for that explanation, Vasillalov.

[vasillalov]

Another thing I forgot to bring in:

In NA engines, some aggressive camshafts have a bit (or a lot) of overlap. Basically the camshafts are designed in such a way that both the exhaust and the intake valves are open for a short period of time. This allows for a slight increase of the speed of incoming air charge through the intake valves and helps to cool the exhaust valves a bit as well. If the head is properly ported and has supporting mods like properly designed equal length intake runners, etc etc, this can create a slight "supercharging" effect during certain rpms.

On a turbo engine, you may not want to have overly aggressive camshafts with big overlap because you will loose boost through the exhaust.

[Joshboody]

Originally Posted by vasillalov

There is no reason to play with the cam angles unless you have upgraded turbos or big turbo. In NA engines, different camshaft profiles allow you for different amount of valve lift and also different amount of time during which a valve is open. All this is done to improve the speed at which air and fuel enter the combustion chamber. The point of it is to maximize the suction effect of the engine (volumetric efficiency). Equal length intake runners, velocity stacks, individual throttle bodies, those are all things that help with volumetric efficiency. You don't just bolt things together and hope for the best. You need to know what your engine is capable of, how much the head flows and heck of a lot of other things before you can maximize power output.

Turbo engines share a lot of these aspects with the NA engines except that you want to maximize the volumetric efficiency when the turbos are delivering the most volume of air. So, our current VANOS is tuned for stock turbos because their parameters are well known. Upgraded turbos and bigger turbos have different flow characteristics and the engine will have a different volumetric efficiency because of that.

I am not saying that playing with the VANOS won't give you any positive results on the N54. I am saying that one has to do a lot of calculations and/or testing on a turbo engine. I'd probably look into upgrading the cams and porting the head first.

I'm sure BMW wasn't focused solely on max performance. We have about 30deg on intake and exhaust to play with, so definitely worth exploring. And when you state "stock turbos" you also mean stock boost, which is not the case with a tune of course. There are negatives to maxing VE for 1 set of parameters, rpm compared to another. For example reversion from backpressure. Or too much overlap in the mid-range. Or decreased dynamic compression. etc.

[vasillalov]

Originally Posted by Joshboody

I'm sure BMW wasn't focused solely on max performance. We have about 30deg on intake and exhaust to play with, so definitely worth exploring. And when you state "stock turbos" you also mean stock boost, which is not the case with a tune of course. There are negatives to maxing VE for 1 set of parameters, rpm compared to another. For example reversion from backpressure. Or too much overlap in the mid-range. Or decreased dynamic compression. etc.

Agreed!

That's why I said there is a lot of calculations and thinking to be done before one can extract anything worth while out of VANOS.

[EastBayE90]

We used to just adjust angles on the dyno and that would show you wether it was adding or taking away power. It's easy if you have lots of dyno time. You just make small adjustments run it and see if it helped or not. It does not require a whole lot of thought.

[Q4P]

Originally Posted by (-(ellblazer420

We used to just adjust angles on the dyno and that would show you wether it was adding or taking away power. It's easy if you have lots of dyno time. You just make small adjustments run it and see if it helped or not. It does not require a whole lot of thought.

The question is; did u affect daily driveability? and did the car idle normal?

[EastBayE90]

Originally Posted by Questforpower

The question is; did u affect daily driveability? and did the car idle normal?

It did not affect daily driving at all because on a Honda we were only tuning the high speed cam(after VTEC engaged). You could tune the low speed cam also but never really messed with it at idle. Idle always stayed the same. With k-pro you could tune the cam angle at any rpm and any load condition. I am assuming that if we were to do it on the N54 we would just tune the cam phasing at higher to midrange rpms and not at idle so it should not affect idle or daily drivability at all.

[vasillalov]

I read up a bit on Double Vanos systems. It looks like we have total of 12 degrees (6 degrees of retard and 6 degrees of advance) of timing adjustments. The angle of the camshafts does not change! What changes is their relationship to the camshaft sprockets. Consider it an advanced variable camshaft gear.

6 degrees will not affect the idle at all.

EDIT:
The idle smoothness usually changes when you increase either the valve lift, the cam lobe degree and you introduce a valve overlap. Since we can't change the valve lift or the cam lobe degree you can expect a normal idle with the N54 and stock cams.

[TMR]

Originally Posted by Clap135

Currently not possible, but don't worry v5 r4.0 is coming out anyday now, which means one week from that day terry will go to isle 7 in radio shack and post directions of how to steal it.

[bulldog_yyc]

Originally Posted by (-(ellblazer420

It did not affect daily driving at all because on a Honda we were only tuning the high speed cam(after VTEC engaged). You could tune the low speed cam also but never really messed with it at idle. Idle always stayed the same. With k-pro you could tune the cam angle at any rpm and any load condition. I am assuming that if we were to do it on the N54 we would just tune the cam phasing at higher to midrange rpms and not at idle so it should not affect idle or daily drivability at all.

i miss kpro - it was awesome!

[Q4P]

Originally Posted by (-(ellblazer420

It did not affect daily driving at all because on a Honda we were only tuning the high speed cam(after VTEC engaged). You could tune the low speed cam also but never really messed with it at idle. Idle always stayed the same. With k-pro you could tune the cam angle at any rpm and any load condition. I am assuming that if we were to do it on the N54 we would just tune the cam phasing at higher to midrange rpms and not at idle so it should not affect idle or daily drivability at all.

Originally Posted by vasillalov

I read up a bit on Double Vanos systems. It looks like we have total of 12 degrees (6 degrees of retard and 6 degrees of advance) of timing adjustments. The angle of the camshafts does not change! What changes is their relationship to the camshaft sprockets. Consider it an advanced variable camshaft gear.

6 degrees will not affect the idle at all.

EDIT:
The idle smoothness usually changes when you increase either the valve lift, the cam lobe degree and you introduce a valve overlap. Since we can't change the valve lift or the cam lobe degree you can expect a normal idle with the N54 and stock cams.

Exactly what I wanted to hear!

Didn't know K-Pro was a Hondata product until I looked it up - Good Stuff!

[Bash]

You do mean Cobb stage 2 right? Man its not just about adding boost/load/timing is it?